REMOVAL OF LEAD (II) IONS FROM AQUEOUS SOLUTIONS BY ALKALIPHILIC BACTERIA HALOMONAS ALKALICOLA EXTNARMIN ZMORROD, HALA S MOUDALLAL, HODA YUSEF, RANYA A AMER AND NAWAL AL HAKAWATI
Lead (II) is among the toxic pollutants that are considered a serious concern since it has adverse effects on the environment and the human health even at low concentrations. The treatment technologies dealing with the removal of this metal suggest biosorption and/or bioaccumulation as an attractive alternative since these methods are ecofriendly and efficient with low cost. In the present study, three halo alkaliphilic bacterial isolates, A1S2, A1S5 and A1Ext were isolated from wastewater effluents of tannery industry located South Lebanon. These bacterial isolates were screened for their ability to tolerate lead (II).A1S2, A1S5 and A1Ext were found to tolerate up to 500, 250 and 1000 mg.L-1 of lead (II) respectively. The most lead (II) tolerant bacterial isolate was studied for its potential to remove lead (II) from aqueous solution. The mechanism of lead (II) removal was assessed using FT-IR measurements and transmission electron microscopy. Several parameters that influence lead (II) withdrawal were optimized. Kinetics of the process was estimated. The bacterial isolate A1Ext was able to remove 27.3 mgg-1 of lead (II).